Inking devices for printing machines



M. MUCH E AL INKING DEVICES FOR PRINTING MACHINES June 16, 1959 4 Sheets-Sheet 1 Filed March 4, 1955 June 16, 1959 M. JAUCH EIAL mxmc DEVICES FOR PRINTING MACHINES' 4 Sheets-Sheet 2 Filed March 4, 1955 4 Sheets-Sheet 3 M. JAL ICH Er AL INKING DEVICES FOR PRINTING MACHINES H ps? IA/IREGEA/A/ 495 yd 47 1,11 (I l rlllllllllllllllllllorlll nunnnlunnnn) v June 16, 1959 Filed March 4, 1955 M. JAUCH EIAL mx'mc DEVICES FOR PRINTING MACHINES June 16, 1959 4 Sheets-Sheet 4 Filed March 4, 1955 Yaw Ayn

United States Patent C) INKING nnvrcns non PRINTING MACHINES Martin Jauch, Konigslutter (Elm), and Horst Kregelin,

Braunschweig, Germany, assignors to Rota-Werke Aktiengesellschaft, Konigslutter (Elm), Germany Application March 4, 1955, Serial No. 492,096

Claims priority, application Germany March 8, 1954 9 Claims. (Cl. 101-122) This invention relates to a method of and a device for inking the ink roller of a printing machine, particularly a stencil duplicating machine, wherein a stencilcarrier, with the stencil, is moved over a number of drums, generally two or three, rotating at the same speed. To one of these drums ink is applied, which passes through the stencil and is transferred to a sheet of paper pressed against it by means of a contact roller.

In known devices of this type, the ink is applied by hand by moving the ink-pot or a container displaceably mounted in the machine, past the inking roller, allowing the ink to emerge by gravity. It is also known to convey the ink under pressure from an ink reservoir to a nozzle supplying the ink, for example by means of a manually operated pump or spring pressure. These devices have the disadvantage of working unevenly, and moreover operating a pump and simultaneously moving the inking nozzle along the roller to be inked is difiicult, the pump in certain cases requiring considerable finger pressure.

For the dyeing of buttons it is known to spray the dye periodically from a nozzle by means of compressed air. But for this a complicated device is necessary, because apart from the dye reservoir and the nozzle and its pipe, it is also necessary to have means for producing the blasts of air and the compressed air pipe. Such a device is therefore unsuitable for the ordinary duplicating machine such as is used in offices.

According to one feature of the invention there is provided a method of inking the ink roller of a printing machine, particularly a stencil printing machine, wherein the ink is discharged onto the roller to be inked under a constant pressure.

According to another feature of the invention a device for carrying out the method comprises a nozzle for discharging the ink onto the roller to be inked, means for displacing the nozzle along the roller and a container for the ink connected to the nozzle, said container also containing a liquid propellant which vaporises at room temperature and produces a pressine in the container in such a manner as to force the ink out of the container to the nozzle.

The liquid propellant may be propane, butane, frigen (difiuorodichloromethane) or the like.

It is also possible, however, to use for the automatic supply of ink, a container which comprises a mixture of ink and liquid propellant, the vapour pressure of which is kept so high by vaporisation when the nozzle valve is opened, that the ink mixture is driven out of the container. In a manner known per se, the mixture of liquid propellant and ink is adjusted so that the vapour developed is sufficient to force the very last drop of ink out of the container. Once outside, the liquid propellant evaporates out of the ink.

The handle which is used to move the container along the ink roller may conveniently be used at the same time 2,890,652 Patented June 16, 1959 to operate the means for opening and closing the nozzle valve.

The nozzle and the handle are preferably mounted for displacement on the longitudinal side of a frame fixed to' the main frame of the printing machine and are connected together, for example by means of a cable line,

in such a manner that when the handle is displaced in one or the other direction the nozzle is displaced simulta-- neously therewith.

Several embodiments of devices for carrying out the method according to the invention are hereinafter described, by way of example, with reference to the accompanying drawings in which:

Figure 1 is a front elevation of two drums of a stencil printing machine mounted one above the other, over Figure 4 shows another embodiment of the ink con-v tainer,

Figure 5 illustrates the means for displacing the ink nozzle,

Figure 6 is a section of the ink nozzle, and

Figures 7 and 8 are sections of two further embodiments of the ink container.

As shown in Figures 1 and 2, two rollers 2 and 3 are mounted one above the other inthe main frame 1 of a stencil printing machine, the lower roller 3 being the ink roller. Over both rollers runs a stencil carrier 4, indicated in broken lines, which usually consists of silk gauze and receives the stencil.

The ink to be applied is contained in a container 5 which can be housed at any convenient place on the machine Where it is not in the way. From this container, the construction of which is described hereinafter, a tube the whole frame, including the displacement mechanism for the nozzle, during multi-colour printing. The frame 6 is rocked about the pivot 7 by means of a handle 9 which is mounted on the frame 6 for displacement in the axial direction of the rollers. By displacement of the handle, the nozzle 10 is simultaneously moved along the roller 3 to be inked. For this purpose a cable 16 is provided as shown in Figure 5, which cable runs over pulleys 17a to 17), which are mounted in the corners of the frame 6. The nozzle 10 is guided on two rods 18, fixed to the frame 6. The cable runs from the point 9a where it is fixed to the handle 9, over a pulley 17a, from thence in the opposite direction and parallel to its first direction to a pulley 17b, then downwards over a pulley to the nozzle 10 to which it is'fixedat 10a. The cable then runs over the pulley 17d, reverses and runs parallel to its former direction to the pulley I 17e, by means of which it is diverted upwards to the pulley 17 1, over which it again runs to the handle 9. 7

roller to be inked in the same direction,

The tube 12 runs over pulleys 21 (Figure .5)

The

spring terision is provided as shown at 13 to keep the tube taut during movement of the nozzle 10.

The nozzle 10 is shown in detail in Figure 6. It comprises a valve piston 11, which, under the action of a spring 11a is urged against a seating provided in. the body of the nozzle 10. The valve piston preferably contains an insert .of rubber or the like to provide a tight seal and is mounted on a rod 11b which projects through the body of the nozzle and rests against 'a cam 20 pivotable about a pin 20a. a contact plate 19 is provided on the main frame of the machine, to extend along the whole length of the roller 2, being preferably curved so as to fit the shape of said roller. When the nozzle 10 is raised as the frame 6 is, rocked about the pivot 7, the cam 20 comes to rest against the contact plate 19 so that the cam is turned in a counterclockwise direction and abuts against the rod 11b in such a manner that the valve piston 11 is displaced from its seating and the inking fluid can then flow through the tube 12, the nozzle 10 and the bore 12a thereof to the roller 3 to be inked.

The ink container as shown in Figure 2 is provided at. an end thereof with a bore into which a cylindrical sleeve 30 is inserted. In this cylindrical sleeve is a member 31, consisting of a flexible material such as rubber, which in its closed position has the shape shown in Fig ure3. At the outer end, the rubber member is turned back round the sleeve 30 and a clamping ring 27 is placed externally round the turned-back portion so as to connect the member 31 firmly to the sleeve 30. The member 31 is provided with an axial bore which communicates with radial bores 29 adapted in the open position of the member 31 to communicate with the interior of the container. In the closed position, these bores 29 are covered by the cylindrical sleeve 30 and the entire ink container is closed.

When the ink container is attached to the machine, a connecting piece 28, fixed to the end of the tube 12, and provided with a piston-like extension 28a, is introduced into the member 31 by means of this extension and pressed in so that the member 31 is extended and its head is forced into the ink container so that the parts take up the position shown in Figure 2. In this position, the inking fluid can pass out of the ink container 5, through the .bores 29 and a bore in the connecting piece 2'0, 28a intothe tube 12.

This closure makes it possible to remove and replace the same ink container, even when it has not been emptied, because when the connecting piece 28 is withdrawn from it, the member 31 again contracts and the container is again closed, the parts assuming the position indicated in Figure 3.

In the case of containers which are only to be placed in position once and are not to be removed again until the contents are used up, the construction shown in Figure 4 may be used, in which a connecting piece 14 is provided on the tube 12, by means of which the tube is screwed into an internally threaded nipple 14a at the bottom of the ink container. The bore of this nipple is closed by a cover 15 when the ink container is full. The cover may, for example, be soldered on and consist of thin metal. When the connecting piece 14 is screwed in, this cover is penetrated and as a result the ink is enabled to enter the tube 12.

The ink container 5 contains a piston 25, which is provided with a lateral cylindrical flange 25a. The piston may be made from a resilient material so that it is urged against the wall of the ink container by the pressure exerted on it internally in the direction of the arrows, thus forming a tight seal. The piston itself iscon- Opposite the cam 20,

the piston a propellant fluid is provided, that is a liquid which vaporizes at a relatively low temperature, particularly at room temperature. Propane, butane, frigen (difluorodichloromethane) and the like are used for preference. The liquid vaporizes and gas forms in the space 34 under a certain pressure against the piston 25 and, if the valve 31 is open, forces the ink through the tube 12 into the nozzle 10.

As the ink used is generally comparatively viscous, it may be advisable to add small amounts of the abovementioned volatile liquid to the ink itself. The ink thus mixed is then softened by the vaporisation of the admixed liquid in the tube or as it leaves the nozzle and 7 containing the ink and the space containing the liquid situated in .such a manner that it matches the shape of The bottom 23 of the of the ink and the liquid is carried out under such con-- ditions that as a result of the vaporization of the liquid, a layer of vapour is formed at the top of the ink c0ntainer, which presses on the surface of the ink and, as soon as the valve is opened, forces it through the tube into the nozzle in the manner described. According to the amount of ink used, more and more liquid propellant vaporizes out of the ink and refills the space above the ink, under pressure, until all the ink has been forced out of the container. Naturally in this case, as in the embodiment first described, the liquid propellant must be measured so that the ink is used up to the last drop. When the container of the aerosol-container type is used, the outlet for the ink must, of course, be at the bottom, the container then having the reverse position to that illustrated in Figure 2.

Figures 7 and 8 show two other embodiments of the ink container. In Figure 7, instead of the piston 25 used in Figure 2 which, in order to obtain a satisfactory seal, requires a precisely shaped cylinder, a tube or the like 35 closed at one end is used which is preferably made of rubber or another resilient material. The open end of this tube is clamped between the cylindrical casing of the container 5 and the cover 22 mounted thereon. The tube rests against the inside of the container and reaches to the closed end thereof. There, as shown in broken lines, it is turned in, and the turned-in portion of the tube, which, together with the end 23 of the container, forms a hollow space, is filled with liquid propellant 33. When this container is in service, the pressure resulting from the vaporisation of the liquid propellant forces the tube upwards against the inking fluid 32.

Figure 7 shows an intermediate position in which the closed end of the tube has been forced about half-way along the container. This position is shown in full lines. It can be seen that the pressure of the vapour extends in all directions thus forming a tight seal between the space propellant or the propellant gas. The gas then fills the space 34. As the container is further emptied, the tube rolls further along and finally reaches the position again shown in broken lines, in which all the inking fluid has been forced out except for a small residue. If necessary even this residue can be forced out, the bottom of the tube curving at the top and matching the shape of the cover of the container.

The embodiment shown in Figure 8 differs from the one shown in Figure 7 only in that here a rubber bladder 36 is used, the open end of which is clamped between the cylindrical casing of the container 5 and the closed end 23 of the container. In this case the bladder 36 is gradually forced from the position indicated in broken lines in Figure 8 to the outlet from the container by the vapor isation of the liquid propellant 33. An intermediate position is indicated in full lines and as more ink is removed the bladder finally assumes the expanded position shown again in broken lines, in which only a residue of ink is present, which can be removed by the closed end of the bladder 36 adapting itself to the shape of the cover 22.

When using a bladder, it is also possible to fill the bladder with ink and then insert it in the container which already contains the liquid propellant 33, clamping the open edge to the casing of the ink container by means of the cover 22. The method of operation is then precisely the same as described above.

We claim:

1. An inking device for a printing machine, particularly a stencil duplicating machine, comprising an ink roller, a nozzle for discharging ink onto said roller, a container for the ink and for a liquid propellant, means adapted to connect said container to said nozzle for supplying ink thereto, said propellant vaporizing at room temperature and produces and maintains a constant pressure in the container so as to force ink out of the container through said connecting means to said nozzle, a valve associated with said nozzle, and means for displacing said nozzle axially along said roller and comprising a handle serving to displace the nozzle and operate said valve.

2. A device for inking the ink roller of a printing machine, particularly a stencil duplicating machine, comprising, in combination with the main frame of the printing machine a rockable frame mounted on the said main frame, a nozzle for discharging ink onto said roller and having a valve associated therewith, a container for the ink, means adapted to connect said container to said nozzle for supplying ink thereto, and for a liquid propellant which vaporizes at room temperature and produces and maintains a constant pressure in the container so as to force ink out of the container through said connecting means to said nozzle, and guide means provided on the longitudinal sides of said rockably mounted frame, the nozzle and the handle being separately mounted for longitudinal displacement along said guide means and interconnected in such a manner that when the handle is displaced in one direction the nozzle is simultaneously displaced in the same direction.

3. A device according to claim 2, in which a stop plate is provided fixed to the said main frame of the printing machine and an actuating member is also provided connected to the valve associated to the said nozzle, said stop plate and said actuating member being arranged so that when the rockable frame is rocked from its normal position the actuating member strikes against the stop plate and opens said valve which is adapted to be closed by the pressure of the ink to the nozzle when the rockably mounted frame is in said normal position.

4. An inking device for a printing machine, particularly a stencil duplicating machine, comprising an ink roller, a nozzle for discharging ink onto said roller, a valve to open and close said nozzle, means for displacing said nozzle axially along said roller and controlling said valve, a container for the ink, an outlet in said container, an outlet valve member located in said outlet and provided with an opening means connecting said container to said nozzle for supplying ink thereto, the connecting means having an end portion thereon adapted to be inserted into said opening of the said outlet valve member and to open said valve member when inserted thereinto, said container having a liquid propellant therein which vaporizes at room temperature and produces a pressure in the container to force ink through said outlet valve out of the container and through the connecting means to the nozzle.

5. An inking device according to claim 4, in which the said valve located in the outlet of the container consists of a body of resilient material surrounded by a cylindrical sleeve of solid and stiif material, the said body being closed at one of its ends and being provided with a lon gitudinal and a transverse bore crossing each other, said transverse bore being normally closed by said sleeve, the body being extended longitudinally by the insertion thereinto of the said end portion of the connecting means so that said transverse bore communicates with the interior of the container and forms a passage for the ink from the container through the connecting means to the nozzle.

6. An inking device according to claim 4, in which the said valve located in the outlet of the container consists of a body of resilient material surrounded by a cylindrical sleeve of solid and stiff material, the said body being closed at one of its ends and being provided with a longitudinal and a transverse bore crossing each other, said transverse bore being normally closed by said sleeve, said body being extended longitudinally by the insertion thereinto of the said end portion of the connecting means so that said transverse bore communicates with the interior of the container and forms a passage for the ink from the container through the connecting means to the nozzle and wherein an end of the cylindrical sleeve projects from the outlet of the container and the corresponding end of the resilient member constituting a second valve folded back over said sleeve end and is clamped thereto.

7. An inking device according to claim 4, in which said container has a cylindrical shape and has an outlet at one end thereof in combination with a piston slidably mounted in said cylindrical container, ink being contained in said container on the side of the piston adjacent to the container outlet, and the liquid propellant being contained in said container on the side of the piston remote from the container outlet.

8. An inking device according to claim 4, in which a membrane-like member is provided to close the opening of said outlet valve and the means connecting said outlet to the nozzle comprises a flexible tube having a rigid end portion with a bore therethrough adapted to be received in the container outlet thereby locating said membrane-like member so that the said outlet is opened when said end portion is inserted thereinto.

9. An inking device according to claim 4, in which the said valve located in the outlet of the container consists of a body of resilient material surrounded by a cylindrical sleeve of solid and stiff material, the said body being closed at one of its ends and being provided with a longitudinal and a transverse bore crossing each other, said transverse bore being normally closed by said sleeve, the body being extended longitudinally by the insertion thereinto of the said end portion of the connecting means so that said transverse bore communicates with the interior of the container and forms a passage for the ink from the container through the connecting means to the nozzle, the extension of the body of said valve caused by the insertion into the longitudinal bore of the said end portion, the transverse bore is uncovered from said sleeve and communicates with that part of the interior of the container in which the ink is contained and forms a passage for the ink to flow through the longitudinal bore and the rigid end portion of the connecting means to the nozzle.

References Cited in the file of this patent UNITED STATES PATENTS 1,996,792 Bystricky et al. Apr. 19, 1935 2,513,455 Cornelius July 4, 1950 2,671,578 McBean Mar. 9, 1954 2,689,065 Schroeder Sept. 14, 1954 2,707,434 Morbardt May 3, 1955 2,860,820 Falligant Nov. 19, 1958 FOREIGN PATENTS 64,950 Switzerland June 18, 1913 

